Hard surface cleaners that perform to clean soils commonly found in bathroom and outdoors environments are known. For example, U.S. Pat. Nos. 5,252,245; 5,437,807 and 5,468,423 disclose reduced residue hard surface cleaner compositions based on solvents, blends of amphoteric, nonionic and anionic surfactants and nitrogenous buffering agents.
U.S. Pat. No. 5,454,984 discloses a cleaning composition comprised of quaternary ammonium compounds, tetrasodium EDTA, a mixture of surfactants and a glycol ether. U.S. Pat. No. 5,585,342 discloses reduced residue hard surface cleaner compositions based on a solvent with a vapor pressure of at least 0.001 mm Hg at 25.degree. C., at least one semi-polar nonionic surfactant and a nitrogenous buffering agent. U.S. Pat. Nos. 5,536,452 and 5,587,022 disclose an aqueous rinsing solution for shower surfaces consisting essentially of a nonionic surfactant having an HLB of 13 or less, a chelating agent and, optionally, an alcohol and/or ammonium hydroxide and/or morpholine. U.S. Pat. No. 5,814,591 discloses an aqueous hard surface cleaner based on either a nonionic surfactant with, optionally, a quaternary ammonium surfactant present in a cleaning effective amount, an organic solvent with a vapor pressure of at least 0.001 mm Hg and ammonium ethylenediamine tetraacetate.
 FNT .sup.1 The entire content of each cited patent is expressly incorporated hereinto by reference.
While at least some of the conventional formulations described in the prior-issued U.S. patents cited above are effective at removing soils and inhibiting the adsorption and coalescence of soils, calcium soaps and/or calcium carbonate on ceramic tile surfaces found in a bathroom environment, they do not demonstrate a high level of efficacy on other non-tile hard surfaces (e.g., glass, metal, vinyl and fiberglass surfaces) commonly found in bathroom and outdoor environments. In fact, some of these conventional cleaning formulations actually dull the finish of glass, metal and/or vinyl surfaces thereby reducing their effectiveness from a consumer's point of view.
It would therefore be highly desirable if cleaning formulations could be provided which are effective at cleaning universally a variety of hard surfaces commonly found in bathroom and outdoors environments. It is towards providing such a needed formulation that the present invention is directed.
Broadly, the present invention is embodied in cleaning formulations and methods by which solid deposition is inhibited on hydrophobic hard surfaces typically encountered in bathroom and outdoor environments without detrimentally affecting the appearance of such surfaces. In this regard, the formulations of the present invention have been found to exhibit reduced spotting and filming.
The formulations of the present invention most preferably include an aqueous mixture of a nonionic copolymer, a polyacrylic acid homopolymer, and a nonionic surfactant. Optionally, a hydrotrope may also be present in the formulation. Preferably, the formulations of this invention have a pH between about 4.0 to about 7.0, more preferably around neutral (i.e., about 7.0). In specific embodiments, the formulations of the present invention include an aqueous mixture of (a) a graft copolymer of polyalkylene oxide with vinyl ester, the graft copolymer having a molecular weight within the range of about 5,000 to 50,000, (b) at least one polycarboxylate selected from the group consisting of acrylic acid/maleic acid copolymers, having a molecular weight within the range of about 1,000 to 100,000 and polyacrylic acid having a molecular weight of from about 1,000 to about 100,000, (c) at least one nonionic surfactant selected from the group consisting of alcohol alkoxylates, alcohol block alkoxylates, and polyoxyethylene/polyoxypropylene triblock surfactants, and (d) one or more water soluble organic solvents.
These and other aspects and advantages will become more apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.